RE: [PATCH v2] refcount: Create unchecked atomic_t implementation

[Reshetova, Elena]

> On Wed, Jun 07, 2017 at 07:58:31PM -0700, Kees Cook wrote:
> > Many subsystems will not use refcount_t unless there is a way to build the
> > kernel so that there is no regression in speed compared to atomic_t. This
> > adds CONFIG_REFCOUNT_FULL to enable the full refcount_t implementation
> > which has the validation but is slightly slower. When not enabled,
> > refcount_t uses the basic unchecked atomic_t routines, which results in
> > no code changes compared to just using atomic_t directly.
> >
> > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> > ---
> > This is v2 of this patch, which I've split from the arch-specific
> > alternative implementation for x86. Getting this patch in will unblock
> > atomic_t -> refcount_t conversion, and the x86 alternative implementation
> > can be developed in parallel. Changes from v1: use better atomic ops,
> > thanks to Elena and Peter.
> 
> Yeah, can we get this in ASAP?  Without having to always incur the over
> this will allow us to convert subsystems to refcount_t broadly.

+1. If this gets in, I can refresh the rest of the patches in net, mm, ipc, block, etc. and send them for review again. 

Best Regards,
Elena